Dexlansoprazole 1, is chemically known as (R)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-1H-benzimidazole, and is the (R)-enantiomer of the proton pump inhibitor lansoprazole. It is currently marketed as KAPIDEX®.

Dexlansoprazole and lansoprazole have activity such as gastric acid secretion suppressing effect and gastric mucosa defensive effect. Both are useful as antiulcer agents and are applied in the treatment and maintenance of patients with erosive oesophagitis and non-erosive reflux disease, i.e. gastro-oesophageal reflux disease (GERD or GORD).
U.S. Pat. No. 6,462,058 discloses a novel crystal of (R)-2-[[[3-methyl-4-(2,2,2-trifluorethoxy)-2-pyridinyl]methyl]sulfinyl]-1H-benzimidazole or a salt thereof useful for an excellent antiulcer agent.
U.S. Pat. No. 7,169,799 relates to a production method of a crystal of (R)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridyl]methyl]sulfinyl]benzimidazole.n′H2O (wherein n′ is about 0 to about 0.1) or a salt thereof, which characteristically includes crystallization from an organic solvent solution or suspension in which (R)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridyl]methyl]sulfinyl]-benzimidazole.nH2O (wherein n is about 0.1 to about 1.0) or a salt thereof has been dissolved or suspended, and the like, and provides a convenient method for efficiently producing an optically active sulfoxide derivative having an extremely high enantiomer excess in high yield at an industrial large scale.
U.S. Pat. No. 7,271,182 discloses a sodium salt, magnesium salt, lithium salt, potassium salt, calcium salt or barium salt of (R)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-1H-benzimidazole, and a pharmaceutical composition comprising the salt. The novel salt is useful as an excellent antiulcer agent.
U.S. Pat. No. 7,285,668 relates to a production method of a crystal of (R)-lansoprazole or (S)-lansoprazole, which includes crystallization at a temperature of about 0° C. to about 35° C. from a C1-4 alkyl acetate solution containing (R)-lansoprazole or (S)-lansoprazole at a concentration of about 0.1 g/mL to about 0.5 g/mL and the like. According to the production method of the invention, a crystal of (R)-lansoprazole or (S)-lansoprazole superior in preservation stability can be produced efficiently on an industrial scale.
WO 2005011692 relates to alkaline salts of proton pump inhibitors and to medicaments comprising these compounds.
CA 2502219 provides a process for producing unstable amorphous benzimidazole compounds having a proton pump inhibitor function, and stable solid preparations for medicinal use containing these compounds which are produced by blending such an amorphous benzimidazole compound with a non-toxic base, such as a basic inorganic salt, forming an intermediate coating layer on the layer containing the active ingredient and further forming an enteric coating layer or a release-controlling coating layer.